The evolution of technology in the area of telephonic communication has resulted in the rapid development and use of mobile cellular phones, to the point that cell phone use is now almost universal. Cell phones were once relatively cumbersome devices, and were severely limited in function in comparison to the cell phones manufactured to the sophisticated technological standards of today. For example, evolving battery technology has enabled mass production of miniaturized cell phones, which are routinely provided to customers for a nominal cost by service providers in exchange for entering a service agreement of a specified term. As a result, the use of cell phones is no longer relegated to high-end consumers and business users. In many instances people are even forgoing the use of traditional hard-wired land lines in favor of cell phones.
A notable trend in telephonic communications enabled by the evolution of cellular phone technology is the rapidly expanding use of text messaging. Text messaging, also referred to simply as “texting”, is a process of transmitting text-based messages from a cell phone or other portable electronic device using the Short Message Service (SMS). Texting has overtaken voice-based cell phone communications for interpersonal communications. According to Nielsen Mobile, a service of the Nielsen Company, by the second quarter of 2008 an average mobile or cellular phone subscriber placed or received 204 traditional voice calls, compared with sending or receiving 357 text messages. A typical teen in the United States currently sends or receives over 1,700 text messages per month, while making or receiving just over 200 voice calls. Clearly, texting has greatly expanded the available opportunities for people to stay in close communication. However, existing cell and landline phone technology remain somewhat limited in certain respects, for example in the potentially unsatisfactory response received by call originators whenever an intended call recipient is either unable or unwilling to receive an incoming call.